It is possible to record conflicting attendance codes for a pupil for the same session and this affects reporting. It happens when an out of school record is created with a start date/time in the past. For example, a pupil not in registration is given an N code by their form tutor. Then slightly later, the attendance officer gets a list of pupils out on a trip and assigns them to a V code for the whole day, using OOS functionality. I don't think she gets any warning message to say that this will create a duplicate code. Having discovered later that there is a duplicate, there isn't any easy way for me to remove it. I think that either there should be a restriction on creating OOS in the past, or else any previous codes in the register should be removed when an OOS is created, with a warning message.
